fungal culture

Sputum: The first early morning sample should be collected after rinsing but before breakfast. Sputum induction with heated aerosol saline suspension may be required if an adequate specimen cannot be obtained. Approximately ½ to 1 ounce of sputum into a sterile, screw-capped container will be sufficient.

Bronchoscopy: Bronchial brushings, biopsy, or bronchoalveolar lavage fluid should be transported promptly to the laboratory in sterile, sealed containers.

CSF: As much CSF as possible should be used for the culture of fungi. Samples should not be refrigerated. CSF is an adequate fluid culture medium that can be left at room temperature or even placed in an incubator overnight if necessary.

Urine: The first early morning urine sample is preferred; random samples are unacceptable. Specimens should be collected aseptically in sterile, screw-capped containers and sent immediately for processing. If a delay in processing beyond 2 hours is anticipated, the urine sample should be placed in a 4°C refrigerator.

Prostatic Secretions: Some deep-seated mycoses, notably blastomycosis, can be diagnosed by collecting prostatic secretions. The bladder is first emptied, followed by prostatic massage. Secretions should be inoculated directly to appropriate fungal culture media.

Exudates: The skin over pustular lesions should be disinfected, and exudates aspirated using a sterile needle and syringe. The syringe also serves as a transport container if the needle is removed. Biopsy of the lesion maybe necessary if the aspirate fails to yield fungi.

Skin, Nails, and Hair: First swab the area of skin to be sampled with 70% alcohol to remove surface bacterial contaminants. Sample the peripheral, erythematous, growing margin of typical “ringworm” lesions scraping with the side of glass microscope slide or edge or a scalpel blade. Infected nails should be sampled from the nail bed. If this is not possible, scrape away the surface of the nail before collecting shavings from the deeper portions. Hairs should be collected from areas of scaling or alopecia.

Tissue Biopsies: Tissue biopsies of suspected sites of infection should be transported in a sterile gauze moistened with sterile saline in a screw-capped container. Do not use tissue homogenizer. If tissue must be reduced use a sterile scalpel and forceps. Carry this procedure out in a sterile petri dish to which a few drops of sterile water have been added.

Blood: The Standard aerobic media is acceptable for isolating fungus, but bottles should be incubated for 10 days to allow for optimal growth of fungus. Follow blood culture protocol.